The investigation was further delayed when cops at the Police Service Area 6 station house did not alert detectives to the crime because they thought Islan Nettles, 21, had suffered only minor injuries in a street brawl, the sources added.

Paris Wilson, 20, was arrested shortly after the Aug. 17 attack and charged with misdemeanor assault and harassment for pummeling Nettles after being teased about flirting with a transgender woman, cops and prosecutors said.

Nettles spent days in Harlem Hospital before being pulled off life support on Aug. 22.

The case proceeded as a simple assault for four days until the Manhattan District Attorney's office learned that Nettles was on life support.

But, after Wilson was arrested, another man walked into a police precinct and confessed to beating Nettles. Police sources were unable to tell DNAinfo New York who that man was, but they said Wilson's mother "coerced" one of her son's friends to take the blame.

Sources in the DA's office said they are still investigating the confession to make sure the wrong person isn't charged. Wilson is likely to face upgraded charges, sources said.

After the men discovered that Nettles and her two friends were transgender, Wilson allegedly began beating Nettles while homophobic slurs were being yelled, according to police. A witness ran into PSA 6 and told cops that Nettles was being beaten up, and two cops raced out and grabbed Wilson, sources said, adding that the witness identified him as the attacker.

Law enforcement sources said that had those cops alerted detectives from the 32nd Precinct, a more thorough questioning of additional witnesses and investigation of the crime scene would have taken place. Instead, it was treated as a simple assault and only days later when the severity of the attack was realized was the investigation ramped up, sources said.

The incident is being investigated as a hate crime.

Nettles' mother, Delores Nettles, said in an interview that she was not contacted by detectives from the 32nd Precinct until two days after the incident.

During Wilson's first court appearance on Aug. 17, prosecutors requested $7,500 bail because Nettles "was unconscious when the police arrived, and the defendant was still assaulting" her, according to court transcripts.

Wilson was identified as Nettles' attacker by a witness, according to the D.A.'s office

Wilson's Legal Aid attorney argued that his client had no contact with the criminal justice system and was a "full-time student in good standing" entering his senior year as a Business Administration major at Buffalo State University next month.

Jerod Dahlgren, Public Relations Director for Buffalo State University, said that a person named Paris Wilson attended the school from the fall of 2010 until the spring of 2013, but did not register for classes this fall.

Dahlgren said the school had not been contacted by the NYPD.

The Manhattan D.A. requested $7,500 bail during the first court appearance but Judge Melissa Crane set bail at $4,000 bond or $2,000 cash after Wilson's attorney argued that he was no flight risk.

Wilson's attorney denied his client's involvement in the incident.

The attorney said as-yet-to-be-obtained video from the precinct station house across the street from where the incident occurred might exonerate his client.

On Aug. 22, Wilson returned to court and prosecutors told Justice Erica Edwards that Nettles' injuries were "much more extensive than we originally believed."

"She is currently on life support and is likely to be removed from life support today. Obviously that will affect the charges that are ultimately lodged," said the assistant district attorney.

But the District Attorney's office did not ask for increased bail and the judge continued the $2,000 package.

Nettles' mother and Harlem LGBT groups have criticized the low bail set for Wilson, saying that it sends the wrong message about the value of the lives of transgender men and women.

"It's troubling that such a terrible attack would happen and there was no awareness and the person got let back out on the street with a small bail," said Carl Siciliano, executive director of the Ali Forney Center which serves LGBT homeless youth.

"This is just another example of transgender people of color being treated like they don't matter."

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